If you have an old 12-string with a big old neck you may find Kysers and Shubbs in the usual form, and the new parrot-beak things simply do not go big enough, either in length or gape. They are aso exensive.

The Shubb Pro-am is cheap to buy, and I have grooved the rubber on mine, as Fielding advised. The screw adjustment also allows the firmness of grip to be precisely adjusted. As a result I find I am usually less out of tune than most 12 strings. The fact that my Hagstrom BJ12E has a neck that would probably winch the Queen Mary out of the water may also help.

I tune to E flat, but may try to get it up to concert with some thinner strings.